Pipe pusher



y :1937- J. H. ABRAMS N ET AL 2,080,104

PIIIDEPUSHER Filed Jan. 6, 195s" 2 Sheets-Sheet 1 May 11, 1937. J. ABRAMSON ET AL PIPE PUSHER File d Jan. 6, 193

2 heets-Sheet 2 Jwm, M WM Patented May 11, 1937.

ITED STATES This invention relates to fluid-operated devices and has particular reference to ,a machine for pushing pipe and the like through the ground.

An important object of the invention is to provide a pusher having a generally improved mode of operationand structural characteristicsin eluding improvedmeans for accomplishing step by step operation, improved latching means, and an improved structural cooperation between the n pusher and the pipe being operated upon.

Other objects and advantages will become apparent from the following description and the ac: companying drawings, in whichf Figure 1 a side elevationof the pusher 10- catedin a pit in its normal operating position; i

. Fig. 2 is a section on'theline 2--2 of, Figure 1; Fig. 3 is a section on the-line 3--3 of Figure, 1;

Fig. 4is a section on the line 4 -14. of Fig. M Fig. 5' is a view similar to Fig. 4 showing the parts in movedjposition; 1 l Fig. dis a fragmentary top view of the rear portion ofthepusher, and.

Fig. 7 is a section on the line 1 'I 10f .Fig. .6.

The present .invention relates toa; device of the general. nature shown in our Patent No. 1,962,228, wherein a pipefor similar article. is pushed throughythe ground in, a step by step fashion by means of ahydraulically perated.pis ton or pistons which are alternately projected marily to improvement in the structural features and mode of operation of such ;.a device Directing attention first to. Figure 1 wherein I a typical pipepus'hin g: installation isportrayed, the unitis shownpositioned ina pit 9 formed in the ground I I adjacent to a concrete pavement I2 or similar surface obstruction under which ,a

pipe is to be pushed, .A base, designated gen-. erally by I3, isYsupported on plank or similar.

supports 14- and IS on the noor of. the pit. The rearend of the. base 13 bears a ainst a backing timber 16 through an intermediate backing plate 11.. A carriage l8"is positioned on the frame l3 and isadapted to be moved toward the right facing Figure 1, through a succession of pushing it strokes.- The forward end or the carria e [B has an abutment" i9 adaptedto bear agalnsta clamp designated generally by'the numeral .2I

normally carried on the pipeQ'This clampniay I p advantageously consist of. a pair otcleyis mem bers22 and 2'3 (Fig. 3) 'pivotedas shownatil i The ends oi the clevis mem bers 22 and 23 opposite the pivot'pin's 24 are slotted as shown at 26 and a threadedpin 2'Iis 5 "pivotally secured jin'the clevis rnember22 as to a cross piece 25.

and retracted, and this invention relates priposite end bearing against a washer H59 whichin "the fluid is released from. the cylinders.

shown at 28 so as to'swing inthe slots 26 to the position shown-in Fig. ,Bwherein a nut 29 may be screwed down to. clamp the clevis pieces against the. pipe so that movementiof-the car riage, i8 willbeltransmittedto the pipe through the clamp 2|. The carriage I8 is providedwith a pair of spaced pistons'3l and 32 positioned at opposite sides of thecarriage in cylinders and 34, the outer ends of the pistons being interconnected by a ,yoke 35 attached .to the pistons by 10 means of ,pins 36and: 31 in a manner. presently to be described in furtherdetail. Injectors 38 and 39 are. positionedon thecarriage adjacent opposite sides thereof and areprovided with plungers 4| and .42 .ofudiflerent displacements 15 so as to pump different quantities of oil into the cylinders of the carriagewhenreciprocated by means of hand1es43and carried onlevers 45.

and 45 and articulated on links and 48 at the: top of the carriage. .The carriage is recessed as shown at 49 intermediate its sides to provide a depression for the reception of the pipe. being acted upon, indicated in ,this instance by thei numeral 20. Handles 5,! and 52 on opposite sides ofthe carriage serve-for manualhandling of the device.-

Referring now more particularly to Figs. 4 and 5, the pistons 3! and J32 carry a head 53.2.1: their inner end towhich a packing 54 isattached by means ofa screwjiand a .plate 56. -,The rear; wardpartof the piston lis of;,smaller.diameter to 30 provide an annular recess 51; within which a' coiled spring 58j is positioned, oneend of:the. spring bearing .against the head 53 and the op turn bears against packing nuts 8| threaded into the end of the cylinder. The injectors 38and .39 are threaded into seats 62 and 63 (Fig.2) and serve to draw oil or other liquid froxn a reservoir 64 by way of. channels and-pass the same into 1 the cylinders 33. and.-34,the cylinders being inter connected by; a channel 66 (Fig, 2)* so .as to, equalize the pressurain the two; cylinders. .As oil is pumped. intogtne cylinders I the carriage; moves: forward from the position shown in Fig. 4 into the position shown in 5, simultane ously compressing the springs 58; which: springs serve to returri or draw the pistons back. into. the cylinders into th position shown inFig. 4 when The base l3 mayadvantageously comprise a railroadrail into which: have been cut'a plurality of equally spacedcross slots 61 on.the..upper sur- I face,.thereof.-T1ie carriage I 8. slides along the i surface of this rail as best shown in Fig.2, the

carriage having a recess 68 for the reception of the upper portion of the rail, and a pair of ribs Openings and 12 in the yoke serve to receive reduced (ads 13 and '74 of the pistons 3| and 32, the openings H and 12 being considerably larger than the reduced ends of the pistons so that the yoke may have a tilting movement thereonin'the manner shown in Fig. '7. The pins 36 and 31 pass through the reducedends of the pistons and through openings 75 and 15 in the yoke which openings are also of considerably greater size than the pins whereby the aforementioned tilting movement of the yoke is permitted. Flanges 11 and 18 on the pistons are so positioned as to bear directly against the forward side of the yoke during a pushing stroke so that the pressure is transmitted directly from the collars to the yoke and not through the pins 36 and 3|. The rear end of the yokev 35 has a downwardly projecting portion 19 adapted to ride along the upthe rail. This latch has a notch engaging portion and a cam portion 85 adapted to cooperate with a cam portion 86 on the yoke 35 so that when the yoke is drawn up to its-forwardposition with respect to the carriage by'action of the springs 58, the cam portion 86 will engage the'cam portion 85 and holdthe slot engaging portion 84 out of engagement with the top of the rail as shown in Fig. '7. 1

In. operation, the pusher is positioned in the pit inithe manner shown in Figure 1, the clamp 2| |9with: the clamp 2|. The 'injectorsare op'er-' 43and are depressed to release the'liquid "in" 7 the cylinders in the mannerdescribed in our is placed on a pipe and the pipe lowered onto the carriage. A guide block B'I'may advantageously be provided to guide the forward end of the pipe. In view of the fact that the upper side of the carriage is open, the pipe'may be lowered directly'into its pushing position regardlessof the position of the carriage 8. The position'of the clamp 2| is then adjusted so'that the forward end of the carriage willbear against the same. With the projection'JB of the yoke 35 engaged i-n'one of the cross'slots of thebase |3 as shown in Fig. 4 the handles 43-and 44 are reciprocated, pumping liquid into the cylinders 33 and 34. Since the pistons 3| and 32 are incapable of backward movement, the carriage is propelled forwardforcing the pipe forward through contact of t he abutment ated 'until the latch 82 drops intothe second cross slot :as shown in Fig. 5. Thereupon the handles above :mentioned patent, upon the release of which-the springs 58 cause the pistonsto move toward the right facing Figs. 4' and 5 'drawingthe" yoke 35 forward until the projection 19 drops into the'nextsucceeding cross slot of the rail.

ward end of the cylinders.

Thereupon the handles 43 and 44 are again reciprocated moving the carriage forward through the next step or until the latch 82 drops into the next succeeding cross slot. In this manner the carriage is moved forward in a step by step fashion pushing the pipe forward in the same manner. When the carriage |8 reaches the forward end of the base |3 it is necessary to return the pushing unit to the position shown in Figure 1 under which circumstances the handles 43 and 44 are depressed permitting the fluid to flow from the cylinders back into the reservoir 64 and the'springs 58 to return the pistons to the for- However, instead of raising the handles 43 and 44 and stopping the return of the pistons when the projection 19 drops into the next succeeding cross slot of the base, the handles are'held depressed until the yoke 35 engages the pawl 82, whereupon the pawl 82 is raised by contact with the cam surface 86 of the yoke. Thereafter the yoke 35 is manually raised and the carriage manually moved backward on the base to its rear position. Likewise, the clamp 2| is moved on the pipe to a new position and the step by step pushing operations previously described are repeated. When a length of pipe has been pushed into the ground sufiiciently to permit of the attachment of a further length of pipe at the rear end thereof, successive lengths of pipe are added as shown in Figure 1.

Our device offers a'number of important advantages over the constructions of the prior art and over our above mentioned patent. For example, it will be noted that in this construction the pipe is pushed through movement of the carriagerather than through movement of the pistonsand the repositioning of the yoke 35 and its attached latch portion is occasioned by operation of the springs 58. The advantage of this mode of operation is the fact that the carriage is caused to move by the very high hydraulic pressure in the cylinder and consequently any binding action which may take place between the base and the carriage tending to interfere with the movement is relatively small with respect to the power being applied. Such binding action frequently occurs because of a small movement of the position of the pipe 20 being pushed, which change in position may result from a variation. in the resistance to thepushing operation along the various sides of the pipe. When this occurs the pipe tends to twist the carriage on the frame, causing a binding action between the base and the carriage. However, since the carriage is moved under the very high force developed by the injectors, this binding action is of minor consequence, It will be seen that the only work required from the springs 58 is'thatof moving the yoke 35 along the top of the base i3 and that'of moving the pistons through the stufiing boxes.

the springs move the pistons freely. Furthermore, it will be noted that the load'on the springs 58 'isrelatively small as compared to the load when the springs are required to move the body as in our previously mentioned patent.

Another advantage of moving the body of the pusher during the pushing strokelies in the fact that the pushing pressure on the pipe need not be released in order to draw up the yoke 35. In other words, with the present construction, as soon as the pawl 82 drops into a slot, the pressure of they fluid in the cylinders may be released and the pipe'held under this tension while the pistons and the yoke are drawn up to the next position. As av result of this, the movement required in prior constructions to take up for resiliency in thepipe and in the. various parts prior to thepoint where an actual mov- 1 ing pressure is applied to the pipe,is not lost. 7 The operation of this. device is thus distinguished Anothenfeature of the invention lies in the fact that the pipe may be loaded directlyonto 3 the-top of the carriage instead of being passed through an opening of somesort as inmany prior art patents. -As a result ofthis construction a'shorter pit maybe employed, since the pit need not have the additional; length required .to

slide the pusher over the pipe. Furthermore,

this construction permits a newlpiece of pipe to be inserted without changing theposition of the pusher unit on the base. -A still further advantageof this construction lies in the factthat the pushing force is applied to one side of the clamp 2| so that it tends slightly to tilt the clamp and increase the clamping action. Another and important advantage of this construction lies in the fact that it permits of considerable lateral movement on the part of the pipe without causing the body to materially bind on the rail or base. In other words, the pipe is relatively free to move within limits to adjust itself to the resistance of the earth through which it is being pushed.

Another advantage of our improved construction lies in the fact that the springs 58 are positioned directly in the fluid cylinders of the device and surrounding the pistons. This tends to materially reduce the overall width of the machine and also eliminatesthe difficulty with for eign matter interfering with the action of the springs. Furthermore, in this construction the springs act on the compression principle and are completely enclosed so that they cannot be conveniently tampered with by unskilled operators.

Another important structural feature. of the device is the construction of the yoke 35 which is loosely supported on the ends of the pistons but so arranged that the pins supporting the yoke on the pistons do not receive the pushing force, this being transmitted directly from the pistons to the yoke. Another advantage of this construction is the arrangement whereby the pawl 82 is actuated by the yoke 35 to permit the pushing unit to be easily moved from end to end of the base.

While we have thus described and illustrated a specific embodiment of our invention, we are aware that numerous alterations and changes may be made without departing from the spirit of the invention or the scope of the appended claims, in which- We claim:

1. A pipe pusher comprising in combination a fluid cylinder, a base for supporting said cylinder through a succession of pushing strokes, a piston in said cylinder, means to hold the piston in a succession of pushing positions, means to inject fluid into the cylinder to move the cylinder, and means for moving the piston with respect to the base and the cylinder to the next pushing position at the completion of a stroke.

2. A pipe pusher comprising in combination a hold cylinder, abase for supporting said cylinder in a succession of pushing strokes, a'plston positioned in said cylinder adapted to engage; said base to predetermine said'pushing strokes; man-- ,ually operable means for selectively injecting Ifiuid into said cylinder at any of aplurality of rates to project said piston at difierent rates of speed to. adaptv the speed and power tothe strength of the operator and the difllculty of the work, and means for moving said piston .onflthe base to the next pushing "positionatthe "(trim-- pletion ofeachstroke. i

3. A pipe pusher comprising in combination a carriage having, at least one fluid cylinder and means to support a pipe 'beingpushed, a'fluld operatedpiston insa'id cylinder, a base including a rail centrally disposed beneath said'carriage to slidably support thesarii, means between saidtpiston andsald rail to secur'e the former in a succession of pushing positions, means acting between said jcafrriageand' said pipe 'for transmitting motion of. theforiner tothe latter, manually operable means on the earriagefor injecting fluid into said cylinder to move the carriage in a pushing stroke, and means controlled .by said manually operable means forretnrr'nng the piston into the cylinder to reposition the parts for the next succeeding pushing stroke.

4. A pipe pusher comprising in combination a fluid cylinder, 2. piston positioned in said cylinder, a base having means thereon for holding said piston in a succession of pushing positions, the cylinder being movable on the piston to exert a pushing stroke on a pipe to be pushed, means for preventing return movement of the cylinder, and spring means acting between the piston and the cylinder for drawing the piston into the cylinder to the next succeeding pushing position.

piston engaging said base at a succession of pushing positions to move the cylinder in pushing strokes, latch means on the cylinder for preventing return movement thereof, and spring means acting between the cylinder and the piston for bringing the piston to the next succeeding pushing position upon release of pressure in said cylinder.

6. A pipe pusher comprising in combination a base, a cylinder movable on the base through a pipe pushing stroke, a hydraulic piston in said cylinder, means for developing pressure in said cylinder to produce relative movement between the cylinder and the piston, latch means on the piston engaging the base at a succession of pushing positions to move the cylinder in pushing strokes, latch means on the cylinder for preventing return movement thereof, and spring means acting between the cylinder and the piston to bring the latter to either the succeeding pushing position or the end of its stroke dependent upon the release of pressure from the cylinder. 7. A pipe pusher comprising in combination a base, a cylinder movable on the base through a pipe pushing stroke, a hydraulic piston in said cylinder, means for developing pressure in said cylinder to produce relative movement between the cylinder and the piston, latch means on the piston engaging the base at a succession of pushing positions to move the cylinder in pushing strokes, latch means on the cylinder for preventing return movement thereof, spring means acting between the cylinder and the piston to bring the latter to either the succeeding pushing position or the end of its stroke dependent upon the release of pressure from the cylinder, and

means for releasing the latch on the cylinder when the piston reaches the end of its stroke;

8, A pipe pusher comprising in combination a base having means defining a succession of pushiiig, positions, a carriage movable on the base througha pushing stroke andhaving laterally spaced fluid cylinders, pistons in said cylinders,

' a latch member connecting said pistons and supported thereon for tilting movement, said latch member having latch means for-engaging said baseatsaid pushing positions to prevent movement of the pistons in a backward direction, latch means on said carriage engaging said base toward the end of said stroke to prevent return movement thereof, and means to bring the pistons to the next succeeding pushing position upon the release of pressure from said cylinders. 9. A pipe pusher comprising incombination a base having transverse slots spaced longitudinally thereof todefine a plurality of pushing positions, a carriage movable on said base through through said annular collar.

10. The combination in a pipe pusher of a base, a carriage n'iov'ablethereon having a central longitudinally disposed depression on its top accessible from the top of the carriage and defining a pushing position of a pipe, manuallyoperable levers spaced laterally onthe top of the carriage on opposite sides of said depression, an abutment at one end of said carriage, a pipe pushing clamp adapted to engage a pipe, and means to movethe carriage forward on the base to urge said abutment against said clamp upon manual operation .of said levers to push a pipe forward through the earth.

JOHN H. ABRAMSON.

EDWIN C. SWANSON. 

